Cherne Industries: 2023 Manufacturing Excellence Awards
Location: Shakopee | Employees: 130 | Specialty: Test plugs and testing equipment for residential, commercial, industrial, and municipal piping systems
In many ways, not much has changed since Lloyd Cherne (pronounced CHER-nee) constructed his first rubber test plug in his suburban Minneapolis garage in 1953. Since then, plumbers have been using Cherne plugs while testing pressure in pipes. They also use Cherne blocking plugs during repairs to prevent leaking when they need to cut pipe.
“We use natural rubber and make them by hand, like Lloyd did,” says Steve Carlson, Cherne Industries’ manager, manufacturing operations. The company does have competition, but according to Carlson, competitors tend to use blow molding in an injection molding machine.
While remaining true to its roots, Cherne’s manufacturing has evolved through the years.
About 25% of the company’s business today is producing much larger plugs for municipal waterworks. The largest plug it makes, which measures 72 by 120 inches, can fill a 10-foot pipe. These plugs are made with natural rubber along with aramid, nylon, or other flexible material to allow the plug to expand to three times its size, then retract.
For many years, Cherne made these larger plugs using molds. Enough met the company’s quality standards to call it a success, but “40% of what we made we couldn’t sell,” Carlson says, and thus had to discard. A few years back, Cherne began automating production of these larger plugs, which significantly reduced rejects. And with skilled labor harder to find, the company has also introduced automation processes into the production of its classic test plugs. “There are still manual pieces to what we’re doing,” Carlson says. “But we’re adding as many process steps as we can so that we can ‘plug and play’ [new workers] in there without having to train them for four months before they can actually make anything.”
Cherne has been growing at a double-digit pace for the past several years. In 2021, it moved into a new 130,000-square-foot facility in Shakopee, about three times the size of the company’s previous Edina location. Cherne now is undertaking two large automation projects, including one for curing its plugs. “It’s a huge project,” says Carlson, “but it’s going to triple our capacity, which is what we need to do.”
